Liberian workers dismantle shelters in an Ebola treatment center in the Paynes Ville neighborhood of Monrovia. Doctors Without Borders closed the center last month because it was no longer needed. Zoom Dosso/AFP/Getty Images hide caption

itoggle caption Zoom Dosso/AFP/Getty Images

A woman cultivates seaweed off the coast of Madagascar to counter overfishing. She's working with Blue Ventures, a business that supports its conservation projects by giving ecotours. Courtesy of Skoll Foundation hide caption

itoggle caption Courtesy of Skoll Foundation

In the 1950s, the World Bank funded the creation of the world's largest man-made dam, the Kariba Dam, which sits on the border of Zimbabwe and Zambia. The construction of such dams can have dire consequences for poor people living near a river, an investigation found. Jekesai Njikizana/AFP/Getty Images hide caption

itoggle caption Jekesai Njikizana/AFP/Getty Images

Colored brain scan of a 17-year-old boy with mad cow disease. The bright yellow spots are a sign that the thalamus is damaged by diseased proteins. Simon Fraser/Science Source hide caption

itoggle caption Simon Fraser/Science Source

At her home in the U.K., Malala Yousafzai reads her letter to the missing Nigerian schoolgirls. Courtesy of Malala Fund hide caption

itoggle caption Courtesy of Malala Fund

A year ago, Lina says her parents took her to Yemen because her grandmother was gravely ill. But when the family arrived, Lina's father announced that she would be getting married to a local man. Renee Deschamps/Getty Images/Vetta hide caption

itoggle caption Renee Deschamps/Getty Images/Vetta

Secretary of State John Kerry and African Union Commission Chairperson Nkosazana Dlamini Zuma signed an agreement Monday to establish the first Centers for Disease Control and Prevention in Africa. The U.S. will provide technical advice and a few staff for the agency. Alex Wong/Getty Images hide caption

itoggle caption Alex Wong/Getty Images

In March, demonstrators in Nairobi demanded tougher punishment for assailants of women and girls. Anadolu Agency/Getty Images hide caption

itoggle caption Anadolu Agency/Getty Images

Rio has hosted competitions that include athletes with physical impairments (above: the open water swim at Copacobana beach for the Rei e Rainha do Mar). But there's never been an event on the scale of the Paralympics. Buda Mendes/Getty Images hide caption

itoggle caption Buda Mendes/Getty Images